package com.hurteng.stormplane.verifcode;

import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;

import java.util.Random;

/*
demo:
 iv_code.setImageBitmap(Code.getInstance().createBitmap());
 realCode = Code.getInstance().getCode().toLowerCase();
*/

public class CreatCode {
    //随机数数组
    private static final char[]CHARS={'2', '3', '4', '5', '6', '7', '8', '9',
            'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'j', 'k', 'm',
            'n', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
            'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
            'N', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' };
    private static CreatCode bmpCode;
    //验证码默认随机数的个数
    private static final int DEFAULT_CODE_LENGTH=4;
    //默认字体的大小
    private static final int DEFAULT_FONT_SIZE=25;
    //默认线条的个数
    private static final int DEFAULT_LINE_NUMBER=5;
    //padding值
    private static final int BASE_PADDING_LEFT=10,RANGE_PADDING_LEFT=15,BASE_PADDING_TOP=15,RANGE_PADDING_TOP=20;
    //验证码的默认宽高
    private static final int DEFAULT_WITH=100,DEFAULT_HEIGHT=40;
    //画布的宽高
    private int with=DEFAULT_WITH,height=DEFAULT_HEIGHT;
    //random word space and pading_top
    private int base_padding_left=BASE_PADDING_LEFT,range_padding_left=RANGE_PADDING_LEFT,base_padding_top=BASE_PADDING_TOP
            ,range_padding_top=RANGE_PADDING_TOP;
    //字符、线条、的个数，字体的大小
    private int codeLength=DEFAULT_CODE_LENGTH,line_number=DEFAULT_LINE_NUMBER,font_size=DEFAULT_FONT_SIZE;
    //变量
    private String code;
    private int padding_left,padding_top;
    private Random random=new Random();

    public static CreatCode getInstance(){
        if (bmpCode==null){
            bmpCode=new CreatCode();
        }
        return bmpCode;
    }
    //验证码图片
    public Bitmap createBitmap(){
        padding_left=0;
        Bitmap bp=Bitmap.createBitmap(with,height, Bitmap.Config.ARGB_8888);
        Canvas c=new Canvas(bp);
        code=createCode();
//        c.drawColor(Color.GRAY);//设置画布的颜色
        Paint paint=new Paint();
        paint.setAntiAlias(true);//去除锯齿
        paint.setTextSize(font_size);
        //画验证码
        for (int i = 0; i < code.length(); i++) {
            randomTextStyle(paint);
            randomPadding();
            c.drawText(code.charAt(i)+"",padding_left,padding_top,paint);
        }
        //画线条
        for (int i = 0; i < line_number; i++) {
            drawLine(c,paint);
        }
        c.save(Canvas.ALL_SAVE_FLAG);//保存
        c.restore();
        return bp;
    }
    public String getCode(){
        return code;
    }
    //画干扰线
    private void drawLine(Canvas canvas, Paint paint) {
        int color=randomColor();
        int startX=random.nextInt(with);
        int startY=random.nextInt(height);
        int stopX=random.nextInt(with);
        int stopY=random.nextInt(height);
        paint.setStrokeWidth(1);
        paint.setColor(color);
        canvas.drawLine(startX,startY,stopX,stopY,paint);
    }
    //生成随机颜色
    private int randomColor() {
        return randomColor(1);
    }

    private int randomColor(int rate) {
        int red=random.nextInt(256)/rate;
        int green=random.nextInt(256)/rate;
        int blue=random.nextInt(256)/rate;
        return Color.rgb(red,green,blue);
    }
    //随机生成padding值
    private void randomPadding() {
        padding_left+=base_padding_left+random.nextInt(range_padding_left);
        padding_top=base_padding_top+random.nextInt(range_padding_top);
    }
    //随机生成文字样式，颜色，粗细，倾斜度
    private void randomTextStyle(Paint paint) {
        int color=randomColor();
        paint.setColor(color);
        paint.setFakeBoldText(random.nextBoolean()); //true为粗体，false为非粗体
        float skewX=random.nextInt(11)/10;
        skewX=random.nextBoolean()?skewX:-skewX;
        paint.setTextSkewX(skewX);//float类型参数，负数表示右斜，整数左斜
    }
    //生成验证码
    private String createCode() {
        StringBuilder buffer=new StringBuilder();
        for (int i = 0; i < codeLength; i++) {
            buffer.append(CHARS[random.nextInt(CHARS.length)]);
        }
        return buffer.toString();
    }
}
